[release/9.0.2xx] Split GivenThatWeWantToRunILLink test class into multiple so Helix can run them separately

[github-actions]

Backport of #44973 to release/9.0.2xx

/cc @joeloff @akoeplinger

[joeloff]

Hmm, looks like we'll need to split off more tests based off the logs

[akoeplinger]

not really, the log says

[Long Running Test] 'Microsoft.NET.Build.Tests.GivenThatWeWantToVerifyProjectReferenceCompat.Project_reference_compat', Elapsed: 00:59:49

so this one test took an hour i.e. it just hung.

[joeloff]

not really, the log says

[Long Running Test] 'Microsoft.NET.Build.Tests.GivenThatWeWantToVerifyProjectReferenceCompat.Project_reference_compat', Elapsed: 00:59:49

so this one test took an hour i.e. it just hung.

I think it's just a really long running test. It tests compat across net45, 46 and every netstandard version from 1.0 through 2.0

[akoeplinger]

the test normally takes just a couple minutes for all combinations, I've retried the build

[RikkiGibson]

@joeloff is this ready to merge?

[joeloff]

yeah, this was just a straight backport, but some branches are being locked for upcoming servicing builds. Let me double check to confirm